Siren



May 15, 1934. MlLEs 1,958,633

SIREN Origmal Filed Nov. 14, 1927 I N VEN TOR.

LISTER H M/Z[5 A TTORNE Y.

Patented May 15, 1934 UNITED STATES PATENT OFFICE Divided and this application October 20, 1930, Serial No. 489,808. Renewed July 31, 1933 4 Claims. (Cl. 171324) This invention relates to motor driven sirens.

The general object of this invention is to provide an improved electric motor driven siren wherein the motor brushes may be retracted from 5 engagement with the armature.

Another object of this invention is to provide an improved motor wherein the brushes are normally out of engagement with the armature and wherein mechanically operated means is provided for causing the brushes to engage the armature when current is directed to the motor.

A further object of the invention is to provide a siren having a, motor driving the rotor of a siren with the brushes arranged so that when the current is cut off from the motor the siren rotor and motor armature may rotate freely without the friction of the brushes on the armature.

Other objects of this invention will be apparent from the following description taken in connection with the accompanying drawing wherein:

Fig. 1 is a central, vertical, longitudinal section through a siren and a portion of a motor showing the rotor and the brush actuating means. Fig. 2 is a section taken on line 2-2 of'Fig.

1 showing the brush actuating means, and

Fig. 3 is a diagrammatic view of the electrical hook up of the motor and brush actuating means. This application is a division of my co-pending 0 application Serial No. 233,094, filed November 14,

In Figs. 1 to 3 inclusive I have shown my invention as embodied in a motor driven siren indicated generally at 50. The motor which is '1 shown as secured to and adapted to actuate the siren is indicated generally at 51. The siren includes a casing 52 having a rotor 53 mounted therein. The motor 51 may be of usual construction except for the brushes and includes an ar- 2 .0 mature 54 and an armature shaft 55 on which the siren rotor 53 may be secured by any suitable means. The shaft 55 is preferably supported in a bearing 56 in the siren casing 52 in addition to being supported in a bearing 57 on the mo- =Tf45 tor but if desired the bearing 56 may be omitted. The motor brushes 58 are shown as mounted in housings 59 which are positioned in apertures 60 in the motor housing. Each of the brushes 58 includes an enlarged head 61 which is posi- 0 tioned within the housing 59 and prevents the brush from being displaced from the housing. Each of the housings 59 is provided with a threaded detachable cap 62 and within the housings g I provide a coiled spring 63 which bears against 55 the cap 62 and the head 61 of the brush and tends to urge the brush head against the bottom of the housing.

For actuating the brushes 58 I provide a pair of rings or actuating members 65 and 66 which are rotatable in grooves 67 and 68 in the motor casing. The rings 65 and 66 are of like construction and are each split as at 69 to facilitate assembly. The rings 65 and 66 are preferably connected by cross bars 70 and are each provided with ears 71 in each of which I provide an inclined slot 72. Pins or operating members 73 on and projecting from each side of the brush housings 59 are positioned in the slots 72 of each ring. The ring 65 is provided with an arm 74 to which a coiled spring 75 is attached which normally tends to hold the arm 74 against the stop 76 so that the rings will force the pins 73 of the brushhousings to the end of the slots 72 farthest from the center of the armature thus raising the brushes out of contact with the armature.

For moving the ring 65 in the opposite direction to move the brush housing pins 73 in the slots 72 towards the armature I provide a solenoid 77 including windings 78 and a core 79. The core 79 is pivotally secured to a link 80 as at 81 and the link 80 is pivotally and slidably connected to an arm 82 of the ring 65 as at 83.

For energizing the solenoid windings as shown in Fig. 3 a wire 85 connects one end of the windings 78 to a feed wire 87 which includes a control switch 88 and is connected to one side of a battery 89. The other end of the solenoid windings is connected by a wire 90 to another feed wire 92 which is connected to the other side of the battery 89.

The feed wire 87 connects to the field of the motor 51 and the other feed wire 92 is connected to the brushes 58 by wires 93. Thus it will be seen that when the control switch 88 is closed the current will flow from the battery 89 through the feed wire 87, to the solenoid windings 78 and thence through the wire 90, to the wire 92 and back to the battery 89. As the solenoid windings 78 are energized the core 79 will be moved and cause the rings 65 and 66 to move against the action of the spring 75 to cause the brushes to move into contact with the armature 54. When the brushes contact with the armature the current from the battery will pass through the feed wire 92 and wires 93 to the brushes and thence to the armature 54 whereupon the motor 50 will operate to rotate the siren rotor 53.

When the control switch 88 is opened the solenoid windings 78 cease to be energized and the tion of current in the field is overcome so thatthe motor rotor and the siren rotor continue to rotate at an operating speed for a considerable time; after the supply of current to the motor has been cut off. This effects a large saving in electric. current which is an item of considerable importance when operating the siren from the" battery of a motor'vehicle. The motor rot'or' act'sa fly wheel to maintain the momentum of the siren" rotor when the current to the motor is discontinued so that the siren rotor coasts atanoperq, ating speed for a long time after the current to the motor, isjcutoff From the foregoing description it will-.be apparent that I haveprovided a novel motor driven siren which.is.compact,idurableiand efficient in use... j i 7 Having thus described my invention, what I claimisz;

1. In an electric motor. including an armature, a pluialitywof: electrical conductive brushes, electricallycoperated power multiplying means. to retain .sa'id brushesin engagement with said 'arma- .turewhen electric current is directed to said mo- .tor and mechanical; means rotatable about the axisoi. said armature toretractsaid brushes from saidarmature. when the currentis not directed to.saidmotor. 7 v i 2. .In combination with a casing, a shaftin said 7 V casing, a motor. for driving said shaiit,-.said motor being secured. to. said casing, said motor including an armature, armature brushes. for said ,motor,

- said brushes being movable towards and from said drawn from said armature and electro-magnetic,

means for moving said disk to move said brushes toward said armature against the action of said resilient means when current is directedto said motor, said electro-magnetic means including a solenoid 3. In combination with a casing, a shaft in said casing, a motor for driving said shaft, said motor including an armature, armature brushes for said motor, housings removably secured to said motor, brush containers movable in said housings, said brushes being disposed in said brush containers, means rjorurging said brushes towards said armatrim, a pair of shiftable disks arranged about said armature, a pin on each of said brush containersfthere beings slot on said disk for each pin, said slots beinginclined, means to normally urge said disk to 'a'p'osition to cause said slots to move said pinsto thereby cause said brushes to be withdrawn from said armature and electro-ma gnetic means for moving said disks'to thereby move said brushes towards said armature.

4'. In'combination with a casing, a shaft-in said casing, a motor 'for driving said shaft, means to secure said motor to said casing, said motor.in-

including an armature, armature, brushes for said motor, housings removablysecured to said motor,

pin, said slots being inclined, means tor normally LESTER :MZILES. 

